If you control a creature with power less than 0, use its actual power when calculating the total power of creatures you control
There could be some interesting synergies with some cards that care about the -9999, but its unclear what those cards are at the moment
Card (Jewelry Bonney) FOIL NNO DON
Must target monsters[edit] Despite not explicitly saying so in their text, almost all Equip Spell Cards must target a monster at activation, which can be any face-up monster on either side of the field unless stated otherwise, and then, following Equip Card rulings, will equip themselves to the targeted monster as an Equip Card when resolving and continuously target the equipped monster as long as it remains face-up on the field
While Yu-Gi-Oh isn't the simplest trading card game out there, there is no denying that overall, it is easier to wrap your head around its rules than that of MTG
At the end of your post-combat main phase, you look at cards equal to the life your opponents lost and pick one to play